POJ 2398 Toy Storage 叉积 和2318基本一样

4 10 0 10 100 0
20 20
80 80
60 60
40 40
5 10
15 10
95 10
25 10
65 10
75 10
35 10
45 10
55 10
85 10
5 6 0 10 60 0
4 3
15 30
3 1
6 8
10 10
2 1
2 8
1 5
5 5
40 10
7 9
0

Box
2: 5
Box
1: 4
2: 1

在poj2138的基础上对线段排序就ok

ACcode：

#include <cstring>
#include <algorithm>
#include <cstdio>
#define maxn 5050
struct  Point{
    int x,y;
    Point (){}
    Point(int _x,int _y){
        x=_x;
        y=_y;
    }
    bool operator<(Point b)const{
        return (x-b.x==0)?y-b.y:x<b.x;
    }
    bool operator==(Point b)const{
        return (x-b.x==0)&&(y-b.y==0);
    }
}p[maxn];
struct Line{
    Point s,e;
    Line(){}
    Line(Point _s,Point _e){
        s=_s;
        e=_e;
    }
    bool operator <(Line t)const{
        return (s==t.s)?e<t.e:s<t.s;
    }
}my[maxn];
int ans[maxn];
int multi(Point p1,Point  p2,Point p0){
    return (p1.x-p0.x)*(p2.y-p0.y)-(p2.x-p0.x)*(p1.y-p0.y);
}
int main(){
    int n,m,x1,y1,x2,y2;
    while(~scanf("%d",&n),n){
        scanf("%d%d%d%d%d",&m,&x1,&y1,&x2,&y2);
        for(int i=0;i<n;++i){
            int a,b;
            scanf("%d%d",&a,&b);
            my[i]=Line(Point(a,y1),Point(b,y2));
        }
        my[n]=Line(Point(x2,y1),Point(x2,y2));
        memset(ans,0,sizeof(ans));
        std::sort(my,my+n+1);
        for(int i=1;i<=m;++i){
            int x,y;
            scanf("%d%d",&x,&y);
            Point tmp=Point(x,y);
            int l=0,r=n,id;
            while(l<=r){
                int mid=(l+r)>>1;
                if(multi(my[mid].s,my[mid].e,tmp)<0){
                    id=mid;
                    r=mid-1;
                }
                else l=mid+1;
            }
            ans[id]++;
        }
        std::sort(ans,ans+n+1);
        puts("Box");
        int cnt;
        for(int i=0;i<=n;++i){
            cnt=1;
            if(ans[i]==0)continue;
            while(ans[i]==ans[i+1]){
                i++;
                cnt++;
            }
            printf("%d: %d\n",ans[i],cnt);
        }
    }
    return 0;
}
/*
4 10 0 10 100 0
20 20
40 40
60 60
80 80
5 10
15 10
95 10
25 10
65 10
75 10
35 10
45 10
55 10
85 10
5 6 0 10 60 0
4 3
15 30
3 1
6 8
10 10
2 1
2 8
1 5
5 5
40 10
7 9
0
*/